A solar cell module is usually a laminated structure and mainly includes a glass layer, an Ethylene/Vinyl Acetate (EVA) encapsulation layer, a silicon cell piece, an EVA encapsulation layer and a solar cell module backboard that are sequentially arranged, wherein the silicon cell piece is sealed and wrapped by two layers of EVA adhesive films. The solar cell module backboard has a main function of electrical insulation, can improve the mechanical strength of the solar cell module and can prevent water vapor from permeating into a sealing layer to affect the service life and the power generation efficiency of the cell piece. Since the solar cell module backboard is arranged on the outermost side of the solar cell module, the backboard is required to have good environmental erosion resistance. Therefore, the manufactured solar cell module backboard must have good wet and heat ageing resistance, high temperature resistance, hydrolysis resistance, corrosion resistance, Ultraviolet (UV) irradiation resisting ability and water resisting capability and have high light reflection capacity at the side of a cell, so as to improve the power generation efficiency of the cell and further lower the cost.
In the prior art, the solar cell backboard is mainly formed by compositing three layers of film materials: a fluorine-containing film with the thickness of 0.020-0.040 mm, a Polyester (PET) film base layer with the thickness of 0.100-0.300 mm and an EVA or polyolefine film or Polyamide (PA) with the thickness of 0.0200-0.180 mm or modified polypropylene by adhesive. The backboard has the following defects that: the backboard is thicker, so that the heat conduction efficiency and the heat resistance are poorer, the reflective rate is low, so the power generation efficiency of the cell is affected; the UV resistance is low, so the material of the surface layer of the cell piece is pulverized too early, yellows, cracks, ages and fails; the water vapor permeation rate is high, so a Potential Induced Degradation (PID) phenomenon is caused; and snail trails are induced, so the power generation efficiency is reduced; the repair for the module is difficult; and the backboard is expensive.